I see her point. I played Art of Balance for the Wii U a while ago. And although it had some clever puzzle design and beautiful graphics... ther was not a real reason to play. Just resolve puzzles. And that's enough reason for some time. But when you have played like 5 or 6 hours from it's total (I don't know how long the game really was), it takes only one or two puzzles you struggle with, and you lost the interest in the game. I quited. There was no reason to continue.
The Witness is not exactly the same, because you have a place to explore and some kind of story aside from puzzles. But it is longer than Art of Balance. A lot longer from what I've been told. It's huge. Besides, the story does not seem to be that extremely interesting thing. So, I could see the same happening when you've played a certain amount of time to this game. You either look up for the solution to continue playing just for inertia... or you quit for pure stress and boredom. And don't get me wrong, I'm not saying that this is what MUST happen in all cases. I'm sure there will be people that will beat the entire game and they will have fun with it 100%. I'm just saying that the author of the video has a point.
This is very different from the Professor Layton series. Here you also have puzzles (some of which are really difficult too)... but at the same time you have a strong story of mystery and in some entries (all of them really) drama. Even if you find a very difficult puzzle, you really want to struggle to solve it, because there is a worthy reward for doing it: continue the story. And even if you get a little tired of that, you have certain minigames that also challenge your mind, but are lot more simple and direct fun to take a rest from the main thing.
In The Witness... is you, this beautiful world, a not that interesting story... and puzzles. Lots of puzzles. You either love being challenged for almost not reward... or you may quit really quickly.
